Door closers



May 8, 1962 e. R. MALLORY DOOR CLOSERS Filed July 11, 1960 2Sheets-Sheet 1 FIG. 2

lNVE/VTOR GELORGE R. MALLORY 87% AT May 8, 1962 G. R. MALLORY DOORCLOSERS 2 Sheets-Sheet 2 Filed July 11, 1960 FIG. 7

m WM w/ M w/ P. S mmmn m M F. V 0 0 mm n United States Patent 3,032,806DOOR CLOSERS George Raeburn Mallory, Sandys St., Blenheim, Ontario,Canada Filed July 11, 1960, Ser. No. 42,171 6 Claims. (Cl. 16-66) Thisinvention relates to improvements in a door closer, and is acontinuation-in-part of application Serial No. 723,559, filed March 24,1958, and now abandoned.

In door closers employing a coacting cylinder and piston constructionand cooperating-spring means therefor, it is usual to apply to thepiston road a specially formed washer-like element generally known as aholdopen Washer which is slidably mounted on the piston rod and providedwith an offset portion designed to engage that end of the cylinderthrough which the piston projects as to cause the washer to cant when itreceives pressure exerted by the end of the cylinder, thus to biteagainst the piston rod and therefore when the piston rod has beenwithdrawn from the cylinder to a desired degree, making it possible tohold the door open. While this is a very desirable arrangement so as togive the user the option of maintaining the door open by means of a verysimple operation, it has distinct disadvantages because due to the factthat the piston rod is cylindrical in character and the orifice in thewasher is circular to conform therewith, the washer is rotatable on therod. The biting of the washer into the rod causes nicks in the rod andmoreover due to the fact that the washer is rotatable on the rod, nickswill be made at different places on the rod and throughout itscircumference as the washer is used from time to time to maintain thedoor closing mechanism in open position. Accordingly, the burredportions of these nicks will engage the edges of the opening in the endof the cylinder through which the piston rod passes with the result thatthe door closer becomes subject to noisy chatter due to nicks in the rodwhich tend to engage the edge or edges of the orifice in the end of thecylinder and interfere momentarily with the smooth free passage of therod through said orifice and which results in intermittently restrainedmovement.

The present invention avoids these disadvantages while maintaining thesimple principle of locking the door closer in open position by means ofa washer which is similarly canted to bite into the piston rod andfunctions in a substantially similar manner.

The invention generally comprises the combination, in a door closerhaving a cylinder, a piston therefor including a piston rod adapted toproject from an orifice in one end of the cylinder and coacting springmeans, of a holdopen washer slidably mounted on said piston rod havingmeans engageable with said end of said cylinder when positioned adjacentthereto for causing said washer to cant into biting engagement with saidrod whereby to prevent relative movement between said rod and cylinder,a means for retaining said washer from rotation on said rod whereby tocause said washer always to cant identically for each desired bitingengagement along the length of the rod and to cause such engagementalways along a predetermined identical path on said rod, said orifice ofsaid cylinder being enlarged in registry with said path to avoidengagement with roughened areas on said rod along said path caused bythe biting engagement of said washer. Preferably the piston rod isformed with opposed fiat sides and the surface of the other two sidesjoining them are curved on a radius and form the predetermined identcalpath for biting engagement with said washer although it is obvious thatother forms of rod could be used to achieve the desired result.

The invention will be fully described in the following 3,032,806Patented May 8, 1962 detailed specification taken in conjunction withthe accompanying drawings which form part of the same.

In the drawings:

FIG. 1 is a top plan view of a door closer, embodying my invention, inmounted position between a door frame and a door, the door beingillustrated fragmentarily and the frame sectionally.

FIG. 2 is a section taken through the piston rod adjacent to one end ofthe cylinder and illustrating the enlargement of the opening in the endof the cylinder through which the piston rod projects.

FIG. 3 is a perspective view of the hold-open washer employed inconjunction with the construction illustrated.

FIG. 4 is a perspective view of the end of the cylinder through whichthe piston rod projects showing the manner in which the hold-open washeris caused to bite into the rod to restrain the rod and cylinder fromrelative movement; and

FIG. 5 is a cross-section taken through an alternative form of pistonrod rectangular in cross-section and showing a type of washer which maybe employed in conjunction therewith for moving into biting engagementwith such rod along a predetermined path.

FIG. 6 is an enlarged fragmentary perspective exploded view of one endof the cylinder of a door closer incorporating a dished end for the,cylinder, a specially orificed bushing for receiving and guiding the rodand a washer for taking the end thrust of the spring; and

FIG. 7 is a fragmentary longitudinal section taken through the free endof the cylinder showing the parts of FIG. 6 in assembly.

Referring to the drawings, A indicates a door closer according to thepresent invention, as a whole, which is shown mounted between the door Band door frame C. The door closer is of generally conventionalconstruction which employs a cylinder 10 enclosing a piston having itspiston rod 11 projecting from one end of the cylinder and it includeswithin the cylinder spring means coacting with the piston and cylinderto cause a door to close. The cylinder is fastened to the door by aconventional bracket 12 piv-otally connected to a bracket head 13 on oneend of the cylinder and the piston rod is placed in operative connectionwith the door from C by a suitable bracket 14 to which the free end ofthe piston rod 11 is pivotally connected. The unit also includes ahold-open washer 15 which is offset at 16 and 17 as a means for causingthe washer to cant when positioned adjacent to the end 18 of thecylinder 10 to engage the piston rod 11 in biting engagement andrestrain it from movement farther into the cylinder 10, when it iscaused to project to a predetermined degree from the cylinder.

According to the present invention a means is provided for restrainingthe hold-open washer from rotating on the piston rod 11 and this ispreferably achieved by forming the piston rod with fiat sides 19 andforming the hold-open washer 15 with a rectangular orifice 20 capable ofreceiving the piston rod in a manner to permit the hold-open washerslidably to move thereon, the opposed sides of the orifice 20 beingdesigned to register with the flat sides of the piston rod as to preventthe washer from rotating on the rod. The opposite sides of the pistonrod are preferably curved on a radius as indicated at 21 such that theedges 22 and 23 of the washer will be caused to bite the crown of theradius of the curved sides of the rod when the washer is caused to cantsuch as in the manner shown in FIGS. 1 and 4, thereby to preventrelative movement between the rod and the cylinder. Thus, bitingengagement between the rod and the hold-open washer occurs always alonga predetermined path, i.e. the curved sides of the piston rod, by reasonof the fact that the washer cannot rotate. The orifice in the closurefor the end 18 of the cylinder through which the piston rod 11 is causedto project is formed with enlargements 24 intermediate opposed edgesthereof and which are disposed in registry with a portion of the curvedsides-of the piston rod 11 or, in other words, in registry with thepredetermined identical path of biting engagement between the washer androd along the length of the latter. Such enlargements create shoulderson each side thereof for engagement with said rod on each side of saidpath as for the normal axial slidable guidance of said rod. Therefore,burred or nicked areas or locations on the rod along said path will nottend to engage the end closure of the cylinder at the edge of theorifice therein which normally has been the case with a cylindrical rodpassing through an orifice of circular character as previously employedin the prior art. In this case, the enlargements 24 in registry with thepath along the length of the rod where biting engagement takes placebetween the rod and washer provide a clearance between the rod and endclosure of the cylinder such that nicked or burred parts of the rod passthe orifice freely and without engagement with edges thereof. Therefore,such burred, nicked or deformed portions of the rod will not, as in thepast, cause the door closer to become noisy and subject to chatter dueto nicks in the rod intermittently engaging the edge or edges of theorifice in the end of the cylinder and which would interrupt,momentarily, the smooth free passage of the rod through said orifice.Moreover, when employing the fiat sided rod with opposite sides curvedon a radius, the crown of the radius provides a narrow path along thelength of the rod for biting engagement such that the enlargements 24 inthe end orifice of the cylinder need not be of substantial extent.

While the above construction is the preferred form of construction, itis obvious of course that a structure of rod and washer might be formedotherwise as to attain the same objective. For instance, the rod mightbe formed rectangular in cross-section, as indicated in FIG. at 25, inwhich case it is desirable to form the washer with the tongues 26projecting into the orifice 27 thereof for biting engagement with therod 25 along a predetermined path within the cross-sectional confines ofthe rod. The enlargements 24 of the end closure of the cylinder wouldtherefore in effect register with the tongues 26 of the washer.Likewise, other structures might be employed to prevent the rotation ofthe hold open washer and achieve the results of the present invention inthe manner set forth.

In some instances when the free end of the piston rod is rotated by theinstaller to line it up with the bracket to which it is to be attached,the internal spring of the door closer pressing on the end of anorificed dished washer element closing the end of the cylinder, if suchis employed, sometimes causes the washer to resist a correspondingturning movement, thus tending to cause the rod to bind at the oppositetop and/or bottom corners of the orifice through which the rod projectsfrom the cylinder. Alternatively, due to the constant compression andexpansion of the spring and the tendency of the end of the spring torotatably retreat or rotatably advance when compressed, this willsometimes cause an end closure Washer where employed to rotate slightlyas to cause the same effect, the end of the spring having a sharp edgewhich tends to dig into the washer since it is of softer steel than thespring. While this occurs infrequently and, therefore, the structuredescribed in connection with FIGS. 1 to 5 is on the average verypractical, even this infrequent occurrence can be avoided by thecombination illustrated in FIGS. 6 and 7.

Here the cylinder 10, formed with the enlarged opening 28 achieved byturning in the ends of the cylinder to form the inwardly directedcircumferential flange 29, is closed by a dished washer 30 having acentral orifice 31 in its dished portion which portion is designed toreceive a bushing 32 of suitable material such as nylon, formed withorifice 33 through which the free end of the piston rod 11 projects. Thebushing 32 is held in position Within the dished portion of the washer31 by means of a thrust washer 34 which assumes the thrust of the spring35 disposed Within the cylinder of the door closer.

The orifice 33 in the bushing 32 is formed identically with thatillustrated in FIG. 2 whereby the orifice 33 of the bushing is providedwith the diametrically opposed enlargements 36 disposed in registry withthe path along the length of the rod where the biting engagement takesplace between the rod and the hold-open washer 37. Consequently, whenthe piston rod 11 is rotated slightly to align the fiat end thereof withthe attached bracket to which it is anchored, the bushing 32 will turnwith it even though such rotational movement may tend to be resisted bythe engagement of the end of the spring 35 with the washer 34-. Inresult, therefore, there is no tendency towards binding between theedges of the orifice 33 of the bushing 32 and the piston rod 11, whereasthe enlargements 36 of the orifice located in registry with the pathalong the length of the rod where biting engagement takes place betweenthe rod and the hold-open washer provide for exactly the same advantagepreviously described to eliminate any tendency of binding and resultingchatter between the opposed curved pistons of the rod burred by thehold-open washer and the edges of the orifice 33 axially alignedtherewith, since such burred portions are clearly straddled by theenlargements 36 of the orifice 33. Though this construction is slightlymore costly than that disclosed in FIGS. 1 to 5, it may be preferred.

It is clear from the foregoing that the present invention in a simplemanner and with substantially no increase in cost or steps inconstruction avoids a deteriorating disadvantage which has been presentin this general type of door closer construction used in the past.

What I claim as my invention is:

1. In a door closer, the combination of a cylinder, a piston within saidcylinder including a piston rod adapted to project from a guidingorifice in one end of the cylinder and axially slidable back and forththrough said guiding orifice, a hold-open washer slidably mounted onsaid piston rod having means engageable with said end of said cylinder,when positioned adjacent thereto, for causing said washer to cant intobiting engagement with said rod whereby to restrain relative axialmovement between said rod and cylinder, means for restraining saidwasher from rotation on said rod whereby to cause said washer to cant,for each desired biting engagement along the length of the rod, andcause such engagement always along a predetermined axially extendingpath on directly opposed surfaces of said rod, said guiding orificehaving four sides and being enlarged on two directly opposed sidesthereof, in an area intermediate the other opposed sides and in registrywith said path, to avoid engagement of edges of said guiding orificewith roughened sections of said rod along said path caused by saidbiting engagement of said washer, said enlargements forming shouldersalong edges of said guiding orifice for sliding engagement with said rodon each side thereof along said path for guiding said rod during itsaxial sliding movement.

2. The combination as claimed in claim 1 in which said directly opposedsurfaces of the piston rod are transversely, outwardly curved wherebybiting engagement between said washer and said rod occurs on the crownof said curved surfaces.

3. The combination as claimed in claim 1 in which the means forrestraining said washer from rotation in cludes a pair of opposedflattened sides on the rod, said washer being formed with an orificehaving straight side edges capable of engaging the flat sides of the rodto prevent rotation of the washer, the two remaining sides of said rodbeing curved on a radius and forming the predetermined path on said rodfor biting engagement with said washer.

4-. The combination as claimed in claim 1 in which the end of thecylinder through which the piston rod projects is substantially closedby a dished, centrally open washer, said dished Washer rotatablycarrying a bushing, the orifice of said bushing constituting saidguiding orifie through which the piston rod projects.

5. In a door closer, the combination of a cylinder, a piston within saidcylinder including a piston rod having a free end projecting from oneend of the cylinder through a guiding orifice and being axially slidableback and forth through said guiding orifice, a rotatably mounted bushingcarried in said end of said cylinder, the bushing passage constitutingsaid guiding orifice for the piston rod, a hold-open washer slidablymounted on said piston rod having means engageable with said end of saidcylinder when positioned adjacent thereto, for causing said washer tocant into biting engagement with said rod whereby to restrain relativeaxial movement between said rod and cylinder, means for restraining saidWasher from rotation on said rod whereby to cause said washer to cant,for each desired biting engagement along the length of the rod, andcause such biting engagement always along a predetermined axiallyextending path on directly opposed surfaces of said rod, said guidingorifice having four sides and being enlarged on two directly opposedsides thereof, in an area intermediate the other opposed sides and inregistry with said path, to avoid engagement of edges of said orificewith roughened sections on said rod along said path caused by the bitingengagement of said holdopen Washer, said enlargements forming shouldersalong the edges of said guiding orifice for sliding engagement with saidrod on each side thereof along said path, for guiding said rod duringits axial sliding movement.

6. The combination as claimed in claim 5 in which a thrust absorbingWasher is included in said cylinder inwardly of and in rotatable bearingengagement with said bushing.

References Cited in the file of this patent UNITED STATES PATENTS

